Service feeders

[Phoenix2024]

I have an inspector that says if you have 2 main panels coming off of one meter, That you can’t use the 85% rule and use 2/0 cu/4/0 Al. That the wire would have to be
Rated for the full 200 amp 3/0 cu / 250mcm Al. Said he read it in the 2005 handbook in a side/foot note.

 

[infinity]

The 83% rule can be applied when the conductors are carrying the entire load of the dwelling. Since you're splitting the load you cannot use the 83% rule but if your calculated load is 180 amps or less the next size up rule would allow #4/0 Al. One other note the conductors between the meter and the panel are service conductors not feeders.

 

[roger]

He is correct. The conductors ahead of the meter (Service Entrance Conductors) can apply the 83% rule but since there is more than one feeder it can't be used to the panels.

(2) For a feeder rated 100 through 400 A, the feeder conductors
supplying the entire load associated with a one-family
dwelling, or the feeder conductors supplying the entire
load associated with an individual dwelling, unit in a two family
or multifamily dwelling, shall be permitted to have
an ampacity not less than 83 percent of the feeder rating.

 

[LarryFine]

. . . if your calculated load is 180 amps or less the next size up rule would allow #4/0 Al.

This. I have never had to use larger than 4/0 al for 200a services, even when split.